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<a name="a2991"> </a>
<h2 align="center">6 - 	 Declarations</h2>
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<h3> 6.1	 Number Per Line</h3>
<p><a name="368"> </a>
One declaration per line is recommended since it encourages commenting. In other words,
</p><blockquote><pre>int level; // indentation level
int size;  // size of table
</pre></blockquote><p><a name="370"> </a>
is preferred over
</p><blockquote><pre>int level, size;
</pre></blockquote><p><a name="614"> </a>
Do not put different types on the same line. Example:
</p><blockquote><pre><a name="15393"> </a>
		      int foo,  fooarray[]; //WRONG!
</pre></blockquote></p><a name="1727"> </a>
<p><b>Note:</b> The examples above use one space between the type and the identifier. Another acceptable alternative is to use tabs, e.g.:
<blockquote><pre>
int	level;	        // indentation level
int	size;	         // size of table
Object	currentEntry;	 // currently selected table entry
</pre></blockquote><a name="a18761"> </a>
<h3> 6.2	 Initialization</h3>
<p><a name="18762"> </a>
Try to initialize local variables where they're declared. The only reason not to initialize a variable where it's declared is if the initial value depends on some computation occurring first.	
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<h3> 6.3	 Placement</h3>
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Put declarations only at the beginning of blocks. (A block is any code surrounded by curly braces "{" and "}".) Don't wait to declare variables until their first use; it can confuse the unwary programmer and hamper code portability within the scope. 
</p><blockquote><pre>void myMethod() {
    int int1 = 0;         // beginning of method block

    if (condition) {
        int int2 = 0;     // beginning of "if" block
        ...
    }
}
</blockquote></pre><p><a name="307"> </a>
The one exception to the rule is indexes of <code>for</code> loops, which in Java can be declared in the <code>for</code> statement: 
</p><blockquote><pre>
for (int i = 0; i &lt; maxLoops; i++) { ... }
</blockquote></pre><p><a name="377"> </a>
Avoid local declarations that hide declarations at higher levels. For example, do not declare the same variable name in an inner block:
</p><blockquote><pre>int count;
...
myMethod() {
    if (condition) {
        int count = 0;     // AVOID!
        ...
    }
    ...
}
</pre></blockquote><a name="a381"> </a>
<h3> 6.4	 Class and Interface Declarations</h3>
<p><a name="207"> </a>
When coding Java classes and interfaces, the following formatting rules should be followed: 
</p><ul><a name="390"> </a>
<li>No space between a method name and the parenthesis "(" starting its parameter list
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<li>Open brace "{" appears at the end of the same line as the declaration statement
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<li>Closing brace "}" starts a line by itself indented to match its corresponding opening statement, except when it is a null statement the "}" should appear immediately after the "{"
</ul><blockquote><pre>class Sample extends Object {
    int ivar1;
    int ivar2;

    Sample(int i, int j) {
        ivar1 = i;
        ivar2 = j;
    }

    int emptyMethod() {}

    ...
}
</pre></blockquote><ul><a name="1733"> </a>
<li>Methods are separated by a blank line
</ul>
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